Cylinder lock-key Combination

Abstract: A cylinder lock-key combination, which comprises a lock body (5) having a lock cylinder (6) which is arranged to control a bolt element (4) connected thereto and which encloses a set of locking discs (7) provided with peripheral notches (13) determining the opening combination, is divided in the longitudinal direction of the lock into two separate locking bar elements (9; 10) which together with the locking discs (7) cooperating therewith are arranged to form two locking units functionally independent of each other and the opening directions of which are opposite one with respect to the other. Transversal extensions (12a; 12b) of a groove (12) in the lock body (5) extend in the opposite direction with regard to the opening direction of the locking unit located at the position thereof thereby allowing movement of the locking bar element (9; 10) in question in said opposite direction without opening the locking unit not to be unlocked. Hence, the cylinder lock can be operated in opposite turning directions by means of two separate keys having quite independent combination cuts.

Description: The invention relates to a cylinder lock - key combination in accordance with the preamble of claim 1 and a locking system utilising the combination. GB-A-1265023 shows a cylinder lock of the above-mentioned kind which can be operated in opposite turning directions by means of two separate keys. This kind of known lock can be employed to lock, for example, two adjacent safety-deposit boxes, access doors or the like, each of the keys being intended to open only a respective one of the boxes or doors in question. In this known solution, the combination cuts of the two keys are located on opposite sides of the axis of symmetry of the keys, respectively. In addition the cuts of the keys are mirror-like so that a so-called O-cut in one key corresponds to a so-called 5-cut in the other key, a 1-cut corresponds to a 4-cut, a 3-cut corresponds to a 2-cut, a 2-cut corresponds to a 3-cut, and so on. Thus when the combination of one of the pair of keys is known, the correct combination for the key capable of operating in the other direction can easily be deduced which constitutes a potential security risk. On the other hand, both keys of the pair act on the same set of locking discs. Following an opening of the locking mechanism using one of the keys, the bolt element attached to the lock cylinder can be turned back beyond the normal lock-closed position all the way into the opening position of the bolt element which should only be possible with the other key of the pair. This is possible because once the set of locking discs have been arranged in the relative positions to open the locking mechanism they can be retained in these positions by turning them using the bolt element. Thus the security for safe locking of this known cylinder lock-key combination is defective. One aim of the invention is to provide an improved cylinder lock-key combination which is operable in both turning directions by means of two separate keys but from which the above referred to defects have been eliminazed. This aim of the invention can be met by means of a combination according to claim 1. In this way it is possible to operate the lock in two different turning directions by means of two keys formed so that the combination cuts of the keys are independent one of the other. Thus knowing the combination of one of the keys of a pair does not permit a deduction to be made as to the combination of the other key of the pair. With a combination according to the invention it is not possible to manipulate the bolt element and the lock cylinder in the way described above either, because when one of the locking units is opened the other locking unit always remains in its locked condition. From the viewpoint of the ease of operation of a combination according to the invention it is of advantage to locate a separating disc between the two locking units, which disc is fixed relative to the lock cylinder and is equipped with a projection separating the two locking bar elements one from the other. The axial lengths of the two locking bar elements, and of the locking units corresponding thereto can, with advantage, be different from each other. As the number of the locking discs in a locking unit affects the pickability of a lock it is possible in this way to better take account of the possibly different security requirements of the two spaces to be locked by the one combination. In practice, the lateral extensions of the groove in the lock body extend in the respective turning direction of the lock cylinder a distance which corresponds to the opening movement of the bolt element connected to the lock cylinder. This movement is of advantage about 90° in each direction. The combination according to the invention preferably comprises at least one key having combination cuts for a locking unit corresponding only to one of the locking bar elements, whereby the location of the combination cuts with regard to the axis of symmetry of the key is chosen according to the opening direction of the locking unit required in each case. The invention also includes a locking system including as locking means a combination as claimed. The invention will now be further described, by way of example, with reference to the accompanying drawings, in which Figure 1 shows a pair of openable doors both locked by one cylinder lock-key combination in accordance with the invention, Figure 2 shows a cylinder lock of a combination in accordance with the invention in longitudinal section, Figure 2a shows, in plan, a part of the lock of Figure 2, Figure 3 shows a section on the line III-III of Figure 2 in a situation in which the lock is ready for an opening movement in the clockwise direction, Figure 4 shows a section on the line IV-IV of Figure 2 in a situation in which the lock is ready for an opening movement in the clockwise direction, Figure 5 shows a section on the line III-III of Figure 2 in a situation in which the lock is ready for an opening movement in the anti-clockwise direction, Figure 6 shows a section on the line IV-IV of Figure 2 in a situation in which the lock is ready for an opening movement in the anti-clockwise direction, Figure 7 shows a key for the innermost locking unit of the cylinder lock of Figure 2 for opening the lock in the anti-clockwise direction, Figures 7a is a section on the line VIIa-VIIa of Figure 7, Figure 8 shows a key for the outermost locking unit of the cylinder lock of Figure 2 for opening the lock in the clockwise direction, and Figure 8a is a section on the line VIIIa-VIIIa of Figure 8. In Figure 1, 1 and 2 indicate openable doors for two adjacent safety-deposit boxes, cupboards or the like, the locking of which takes place by means of a single cylinder lock 3 and a bolt element 4 attached thereto and which in its base position as shown locks both doors. The bolt element 4 has a first wing 4a which locks door 1 and a second wing 4b which locks door 2. The element 4 can be turned by two separate keys in the opposite turning directions through about 90° into respective positions in which one or other but not both of the doors 1 and 2 can be opened, the non-opened door remaining locked. From Figure 2 it can be seen that the cylinder lock 3 comprises a lock body 5, and inside it, a turnable lock cylinder 6, which houses a set of locking discs 7 each provided with peripheral notches 13 and separated from each other by means of intermediate discs 8. In the conventional way, the locking discs 7 are symmetrical so that the cutting range for the peripheral notches 13 determining the opening combination of the lock is located on both sides of the axis of symmetry A (see Figures 3 to 6) of the discs. In Figures 3 to 6 the possible positions for the peripheral notches 13 are shown one in full line and the others in dotted lines. The conventional locking bar of the lock is, in the illustrated embodiment, divided in the longitudinal direction of the lock into two separate locking bar elements 9 and 10, which together with the locking discs 7 cooperating therewith are arranged to form two locking units which are functionally independent of each other and the opening directions of which are opposite one with regard to the other. The locking bars 9 and 10 are located, in their locked position, partly in a groove 12 provided in the inner surface of the lock body 5 and partly in a slot 17 provided in the lock cylinder 6 thus preventing turning of the lock cylinder 6 with regard to the lock body 5. The set of locking discs 7 is turnable by means of a key of the lock inserted into the semi-circular opening in each disc 7 into positions in which the peripheral notch 13 of each locking disc 7 of one or other of the locking units move to provide, at the location of the respective locking bar 9 or 10, a uniform channel into which the locking bar in question can enter, thereby releasing the locking cylinder 6 to turn relative to the lock body 5 in the direction allowed for that key. At the same time, the turning movement of the cylinder 6 is transferred to the bolt element 4, via force transmission member 16 attached to the lock cylinder 6. Thus only one of the locking units opens at a time. In order that the about 90° opening movement of the bolt element 4 in one locking unit can be made independently of the other locking unit, the groove 12 for the locking bar in the lock body 5 comprises respective extensions 12a and 12b extending transversely with respect to the elongate direction of the locking bar for each of the locking bar elements 9 or 10 so that the extension 12a or 12b extends in the opposite direction with regard to the opening direction of the respective locking unit, whereby each extension allows movement of the locking bar element 9 or 10 in question in said opposite direction without occasioning an opening of the locking unit. The lock cylinder 6 is also provided with a separating disc 11 which is immovable relative to it and is equipped with a protrusion lla arranged between the locking bars 9 and 10 in order to separate them one from the other. The shape of the disc 11 can be seen in Figure 2a. The locking discs 7, for their part, are each equipped with a protrusion 15 which, together with two stop surfaces 14 in the lock cylinder 6, restrict the turning range of the locking discs 7 within the lock cylinder 6 to a turning angle of about 90°. In order to open one of the locking units, the set of discs 7 must first be turned by means of the correct key inserted into the lock in the respective end position defined by the turning range of the locking discs, depending on the particular opening direction which applies to that locking unit. In the case of Figures 3 and 4, the locking unit controlled by the locking bar element 9 can be opened by turning the locking discs 7 in the clockwise direction. Figures 8 and 8a show a key 19 suitable for this purpose and include combination cuts 19a in a mid-portion of the key shank. After opening of this locking unit, the bolt element 4 can be moved by turning the key 19 further in the same direction. At the same time the locking bar element 10 moves along the transverse extension 12b thereby enabling this turning movement (cf. Figure 4). Similarly, Figures 5 and 6 show the initial position for the opening of the locking unit controlled by the locking bar element 10. Opening now takes place in the anti-clockwise direction by turning a key 18 that is shown in Figures 7 and 7a. In this case combination cuts 18a in the outer end of the key shank line up the peripheral notches 13 of the respective locking discs 7 directly under the locking bar element 10, whereby the locking unit in question is released. Now the transverse extension 12a allows the locking bar element 9 and the locking discs 7 corresponding thereto to be turned through a turning angle required for the opening of the bolt element 4. As will be apparent from Figures 3 and 4 when compared with Figures 5 and 6, when the keys 18 and 19 are used in successive order so as to operate the two locking units of the cylinder lock 3 in turn, the set of discs 7 must first be turned through 90° in the opposite direction, so as to rearrange the locking discs 7 into a base position, before operating the lock in the desired opposite opening direction. In order to know how to withdraw the key in the correct position out from the lock after locking is accomplished, the lock can be provided with an identification for the base position. Solutions known as such can be applied for this purpose. For example the inner end of the lock cylinder 6 can be provided with a spring-loaded ball which together with the groove 12 in the lock body 5 indicates the removal position for the key. As is apparent from Figures 7 and 8 the combination cuts 18a and 19a in the keys 18 and 19 are operable in opposite turning directions, since they are formed on opposite sides of the axis of symmetry B of the key. The invention is not to be considered as being limited to the embodiment illustrated, since further variations thereof may be feasible within the terms of the following claims.

Claims: A cylinder lock-key combination, which comprises a lock body (5) having a lock cylinder (6) which is arranged to turn a bolt element (4) connected thereto and which cylinder (6) encloses a set of locking discs (7) provided with peripheral notches (13) located within a cutting range extending on both sides of an axis of symmetry (A) of each, locking disc (7) and determining the opening combination of the lock, and a locking bar (9; 10) which in a locked position thereof is located partly in a groove (12) provided in the inner surface of the lock body (5) and partly in a slot (17) provided in the lock cylinder (6) to prevent turning of the lock cylinder (6) with respect to the lock body (5), the locking discs (7) being separately turned by means of the key of the combination into positions in which the peripheral notches (13) thereof are aligned at the position of the locking bar (9; 10) to form a channel into which the locking bar (9; 10) enters thereby releasing the lock cylinder (6) to turn with respect to the lock body (5), characterised in that the locking bar (9; 10) is divided in the longitudinal direction of the lock into two separate locking bar elements (9; 10) which together with the set of locking discs (7) cooperating therewith define two locking units functionally independent one of the other and the opening directions of which are opposite with respect to one another, and in that said groove (12) located in the lock body (5) for the locking bar comprises a transversal extension (12a; 12b) for each of the locking bar elements (9; 10) so that each extension (12a; 12b) extends in the opposite direction with regard to the opening direction of the locking unit located at the respective position thereof, thereby allowing movement of the respective locking bar element (9; 10) in said opposite direction without opening the locking unit not being turned in its opening direction. A combination according to claim 1, characterised in that a separating disc (11), which is fixed relative to the lock cylinder (6), is arranged between said two locking units, said separating disc (11) being equipped with a projection (lla) separating the locking bar elements (9; 10) one from the other. A combination according to either of the preceding claims, characterised in that the axial length of one locking bar element (9) and of the locking unit corresponding thereto, is different from the axial length of the other locking bar element (10) and its locking unit. A combination according to any one preceding claim, characterised in that each transverse extension (12a; 12b) of the groove (12) in the lock body (5) extends in the direction of the turning movement of the lock cylinder (6) a distance which corresponds to the opening movement of said bolt element (4) connected to the lock cylinder (6). A combination according to any one preceding claim, characterised in that it comprises at least one key having combination cuts (18a; 19a) for a locking unit corresponding only to one of the locking bar elements (9; 10) and in that the location of the combination cuts (18a, 19a) with regard to the axis of symmetry (B) of the key is chosen according to the opening direction of the locking unit required in each case. A locking system for locking openable doors (1; 2) for two adjacent safety-deposit boxes, cupboards or the like, including as locking means a combination in accordance with any of the preceding claims and comprising a separate key (18; 19) for each locking unit of the cylinder lock (3) of the combination, characterised in that a bolt element (4) is connected to the cylinder lock (3), said bolt element (4), in one position, being arranged to lock both the doors (1, 2), whereby either one of the locking units can be opened with its respective key and said bolt element (4) be turned into a position, in which the respective one of the doors can be opened but not the other door.

Inventors: MIELONEN PEKKA, MIELONEN, PEKKA
Applicants: ABLOY SECURITY LTD OY, ABLOY SECURITY LTD. OY
Application year: 1994
Main classification: E05B21
IPC codes: E05B35, E05B9, E05B21, E05C7